The term Gender Identity refers to?

Gender identity is how someone personally experiences and understands their own gender. It’s their internal sense of being male, female, neither, or somewhere in between. Unlike gender expression, which is about how someone presents themselves outwardly, gender identity is deeply personal and may not match their assigned gender at birth, how they express themselves, or their sexual orientation. Recognizing this difference is key to creating a more inclusive and respectful environment.

Source: https://emilms.fema.gov/IS-0020.24/#